A-LevelBiologyBiological moleculesFeb/Mar 2023Paper 1 Q71 Mark
To estimate the concentration of glucose in an unknown solution, equal volumes of a range of known concentrations of glucose were each mixed with the same excess volume of Benedict's solution. After mixing, the solutions were placed in a thermostatically controlled water-bath at 90 °C for three minutes. The unknown solution was then treated in the same way and the colours of the known and unknown solutions compared. What is the independent variable in this procedure?
Aconcentration of glucose
Bfinal colour of solutions
Ctemperature of water-bath
Dvolume of glucose solutions
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The correct answer is A. This question tests the candidate's understanding of biological molecules within the Biologysyllabus. The examiner's mark scheme requires...
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